Implantable stimulators are often used to treat a variety of medical disorders by providing electrical stimulation pulses via one or more electrodes placed at a desired stimulation site within a patient. The electrodes are typically disposed on one or more leads that are coupled to the implantable stimulator.
One type of implantable stimulator includes an implantable pulse generator (IPG) configured to provide spinal cord stimulation to a patient. At least one stimulating lead with one or more electrodes disposed thereon may be coupled to the IPG. In this manner, the lead may be implanted epidurally near the patient's spine and the IPG may be implanted in a surgically convenient location (e.g., within a subcutaneous pocket created within the torso of the patient). The IPG may then generate and deliver electrical stimulation pulses via the one or more electrodes to the spine in accordance with stimulation parameters configured to treat a particular medical disorder.
To facilitate coupling of a lead to an implantable stimulator, the stimulator may include a header assembly having a receptacle configured to receive a proximal portion of the lead. After the lead has been inserted into the receptacle, a set screw may be tightened against the lead to secure the lead in place.
However, it is often difficult to prevent body fluid and tissue ingress onto or around the set screw. These fluids and/or tissues may cause corrosion and/or premature failure of one or more components within the stimulator. They may also possibly prevent the set screw from being released in future procedures. In systems where the set screw is an active electrical element, fluid ingress may create accessory electrical current pathways that could reduce the effectiveness of the therapy provided by the stimulator or cause harm to the patient.